Speed-indicator.



P. s. CRAVBN. SPEED INDICATOR.

APPLICATION FILED APR. 30, 1912.

FRANCIS S. CRAVEN, OF THE UNITED STTS NAVY.

SPEED-INDICATOR.

Specification of Letters Patent.

at-ented Feb. 4, 1913.

Application filed April 30, 1912. Serial No. 694.194.

T @ZZ whom 1' t may concern: A

Be it known that I, F RAXCIS S. CRAVEN, ensign, United States Navy, acitizen of the United States. at present attached to the l?. S. S.Uta/1, have invented certain new and usefiil improvements inSpeed-Indicators; and l do hereby declare the following to be a full`clear, and exact description of the invention, such as will enableothers skilled in the art to which it appertains to make and use thesame.

This invention relates to speed indicators, 4and has for its object toproduce a device 01 this nature capable of general use, which will besimple in construction, certain in action. and comparatively inexpensiveto manufacture.

To these ends the invention consists in. the

novel details of construction and combina- 3@ tions of parts more fullyhereinafter dlsclosed and particularly pointed out 1n the claims.

Referring `tothe accompanying drawings forming a part ofthis'specitication'in which 8@ like numerals designate like parts 1n allthe views :--Figure 1 is' aplan View of 'a speed indicator made inaccordance with my 1nvention; Fig. 2 is an elevational sectional view ofthe parts shown in Fig. 1; and, Fig.' 3 is a suitable form of reducinggears adapted to be used in connection with my invention. f f 1indicates any suitable base upon Which the mechanism is mounted; 2 adisk operated by a clock mechanism. notA shown, but which 'makes arevolution in a predetermined time; 8 a sunken or cut out portion of thedisk 2 to accommodate Ithe totalizing wheel 4; 5 a friction Wheel ordiskadapted so tol Contact with the disk 2: G'anot-her fric;r tion wheelor disk similar to the disk 5 and also adapted to contact with the faceof the disk 2; 7 a shaft carrying the disk 5 and the gearS; l9 a similarshaft carryingthe disk 6 and a gear 10; 1l a pinion mounted in thetotalizing Wheel 4 and meshing with the gears 8 and 10, as shown; and 12an elongated pinion with Whichthe wheel 4 enl ages. 13 is a shaftcarrying the pinion 12 mounted in bearings on the support 1, as shown.and carrying at one end 'a gear 14.

15 is a shaft whose revolution-s it is desired to indicate: 16 a gearmounted on the 55 shaft 15; 17 a totalizing Wheel; and 18 pinion meshingwith the gears 14 and 16 .f mounted in the wheel 17.

18L is a gear meshing with the Wheel 1T; 19 a shaft carrying said gear18a on which is mounted the bevelgear 20, meshing with the bevel gear21, mount-ed on the screwihreaded shaft 22, passing through the nutlikeextension 23 of the U-shaped frame 24. provided with the bearing 25 toaccommodate the shaft. 7, and the bearing 2G to accommodate the shaft 9.The said frame 24 is preferably.further provided with a spring 27adapted to take under the stationary plate 28 secured to the base 1, asbest illustrated in Fig. 2.

The nut-like extension 23 is provided with rack teeth 30, meshing withtheA sector 3l. mounted on the pivot 32, which also carries the point-er33 playing over the scale 34, as shown.4

35.'F ig. 2,y representsan extension from the plate 2 which may servetosuitably connect the said plate with the clock mecha-` nism. not shown.

.is will appear below. it will bte-sometimes desirable to'substitutehfor the gears 14,16l and 18, between the shafts 13 and 15, areducing gear such as is shown Fig. 3. The gear illustrated in this saidfigure consists of a pinion 40 carried by the shaft 15, mesh Ving withthe pinion 41 of larger diameter lhanfthe pinion 40. carried by the studshaft 42, which also carries the pinion 43. which is smaller in diameterthan the pinion 41, and which in turn meshes Withvt-he larger ninion 44carried on the stud shaft 45, on which is mounted the smaller pinion 46meshing'with the larger gear 47 ycarried by the shaft 13. v

The shafts 13 and 15 are adap'ted to move independently of each other.as best indicated in Fig. 3. and the stud shafts 42 and 45, asWell'as-the pinions 4l. 43. 44 and 46 are carried by the totalizingWheel 50 corresponding tothe wheel 17. as shown.

The operation of my .speed indicator is as follows: The disk 2 beingdriven by the minute arbor. for example, of la clock mechanism, notshown, and adapted to make say one revolution in about ten minutes, willdrive the friction Wheels ordisks 5 and 6 in opposite directions, aswill be vclear from Fig. 1 .of the drawings. I-f the s aid disks @and 6contact with the driven disk 2 at "points equally distant from thecenter of their respective beveled gears 8 and, 10 in.

\ opposite directions and at the same speed.

Seid dik aa is evident that they wai tur-n /Theresult Will be that thebevel pinion 11 will move around its axis,.\vitl'out exerting. anyturning effect on the totalizing wheel 4 at all. On the other hand,should the disks 5.aiid 6 be moved acrossthe face of the disk 2, so asto Contact at points not equally distant from the center of the saiddisk2, then it is evidentthat since the` totalizing wheel 4 is looselymounted on the shafts 7 an'd'9,

` it Will be turned an'iangular distance equal to the difference inangular motion of the said bevel gearsS and 10. This said difference vofmotion will -of course, be transmiting turned in the direction of thearrow, will turn the'pinion 18 on the gear 14 as a track,- and cause thetotalizi'n-g wheel 17, loosely mounted onfthe shafts 13 and 15, t-o alsoturn in the direction of "the arrow. The rotation of thewheel`17vvillturn the gears 18,20 and 21, Land cause the screw-threadsl 51 on the,shaft 22l to move the member 23 i "and yoke 24 bodily across the VAfacelof the' disk 2, and thereby cause the rotations of 6 now being ofdifferent values, and in opthe disks 5 and 6 to be unequal, as statedabove. The', speeds of the said disks 5 and posits directions, thetotalizing Wheel 4 will turn the pinion12 and the gear 14' in adirection opposite that of the gear 16, and thereby lessen the speed ofthe totalizing wheel 17 However, so long as the wheel 1,7,moves at all,the screw shaft' 22 wil 1 con'- tiue .to revolve and continue 'to' movethe voke 24 and vt-he.disks 5 and 6 across the face of the disk 2,and-thereby increase the difference in motion between the -gears 8 and10 and the speed of the totalizing wheel ,Iquently soon be' reached whenthe speed of 4, which in turn will increase'the speedof the gear 14. andlessen the speed of the to#I talizing Wheel 17. A point will consei. thevWheel 17 will be zero, and `,thereupon ,the'radial movement of thefriction wheels -ses 5 and 6 will cease. As the'yoke 24 bodily movesacross the-face of the disk 2,--its rack teeth 30 will ,move the sector31 aroundits pivot 32, and'viiill therefore move the pointer 33' overthe scale 34. The said pointer will continuev to moveso long as the4disk 17j moves, but when the speed of 'the shaft 13' in 4the instancecited, equals'the speed ofthe shaft 15, the wheel 17 will come to rest,Titia-'of course, will cause the saidpointer 33 t'o come to rest atvthatpoint on the fsoale 34, which indicates the speed of` i ligosaai theshafts 13 and l5, althoughthe shafts 13 i 'and 15 are stillrevolv/ing.The pointer will remain at the proper indication denoting the speed 'ofthe shaft 15 so long as the speed of the said shaft remains constant,but' when this said speed increasesvor decreases, the pointer 'w1llmovecorresponding distances farther along the scale, or will moreyliiaclward over the lscale, as the case may bc.

Should the motion of the Shaft 15 be rcversed, its speed vvi'll firstreach zero, when of course the speed of the shaft 13. Will also reachZero, and the pointer will likewise indicate zero. As the speed of-the'shaft 15 next increases in t-heopposite direction, the rotations ofthe shaft' 13 Will likewise increase in a direction opposite Atoitsoriginal motion, and the pointer avill indicate the proper' speedonftlie other side of the scale 34. In practice, however, the speed ofthe shaft 15, Which it is desired to measure, is very much greater thanany convenient constant speed at which the shaft .13 can be run. andtherefore, itbis found necessary to -employ 'a reducing gear between theshaft 15 and the shaft 13. There are many forms of suitable reducinggears for this purpose, and one of such forms is illustrated in Fig. Inthis ligure, vmotion ofthe shaft 15 may be transmitted to the Wheel 50,which corresponds to the Wheel v17, through the gears described above,and this motion may be reduced f in any suitable\ fixed ratio so thatalthough the rotations of the shaft 15 may be very'v high,`yet they willbe counter-y acted by the slower motions of the shaft 18, in the mannerabove disclosed. v

The yoke 24 and the friction disks 5 and 6 are steadiedxin theirmovements by means of the spring 27 and roller 52, which takes under theplate 28, and the -ball bearings 53 under the disk 2 serve" to decrease`fric tion.' l. .It is obvious that those skilled in this art may varythedetails of construction as'well as the arrangement of partswit-houtdeand therefore, I do not Wish to be limited to the above disclosure,except as may be requiredy by the claims.

What I claim is 1. In a speed indicator, of a disk adapted to be drivenat a'predeterminedl speed: a plurality of oppositely driven diskscontrolled by said disk; a totalizin-g Wheel driven by the difference inmotionof said disks; a shaft the revolutions of which it is ,desired toindicate; connections between said totalizing wheel and said shaftcomprising a second totalizingwheel; means for moving said oppositelydriven disks over theface of said first mentioneddisk;

lparting from the yspirit of my invention,

the combination and connections between said second totalizl ing-wheel'and'said moving means, substantially as described. I

2. .In a `speed indicator; the combination of a disk adapted to bedriven at a known speed; a shaft whose revolutionsit is de-` sired toindicate; 'friction disks contactingv with said driven disk andmovable'radially thereof; connections between said friction disks andsaid ishaft;gear1ng connectlons between said 'first/named connectionsand said friction disks; and a .pointer connected 'to be actuated by theradial movement of said friction disks to indicate at all times thespeed'of said shaft, substantially as described.

3. In a speed indicator, the combination of a disk ada ted to be drivenat a known speed; a sha t whose revolutions it is desired to indicate;friction disks contacting with said driven disk; means connecting saidshaft with saidfriction disks compristion it is desired to indicate;connections comprising a totalizing wheel between said friction wheelsVand said shaft; a movable yoke for` supporting and moving said frictionwheels; connections between said totalizing` wheeland said yoke formoving the latter; anda pointer operated bythe movement of said yoke forindicating the speed, substantially as described. y

5.v In a speed indicator,.the combination of a disk adapted to be drivenat a constant speed; friction wheels movable on the face of said disk;-a shaft whose speed' of revolution it is desired to indicate;connections comprising a pair of differential .gears each having atotalizing wheel between said friction wheels. and said shaft; a.movable yoke for supporting'and moving said friction wheels; connectionsbetween one of said totalizing wheels and said yoke for moving thelatter; and a pointer-operated by thel movement of said yoke forindicating' the speed; substantially v'as described.

6. In a speed indicator, the combination of a diskadapted to be'rotatedby 'a clock; a pair vof friction Wheels contacting with and `driven inopposite directions by said disk; a differential gearing'k operated bysaid Wheels; a pinion and shaft operated by said gearing; a second shaftwhose rotations it is desiredto indicate; a differentialgearing betweensaid first and secondshafts.; a yoke y carrying said friction wheel-sand adapted `to move the sameY across the face of said disk; connectionsbetween said second` gearing and said yoke; and a pointer adapted to bemoved by said yoke, substantially as' described. v-

In testimony whereof, I aHX my signature in presence `of two witnesses.

FRANCIS S. CRAV-EN.

Witnesses:

GooLD H. BULL,

SAMUEL H. M IDDLENN.

